Coal combustion residuals, leachate and wet ash wastes solidification devices, kits and assemblies

ABSTRACT

Environmental waste solidification devices, system, kits and methods are shown and described. Absorbent compositions for solidification of environmental wastes are shown and described. In one example, the composition includes an amount of sodium polyacrylate polymer mixed with another non-polymeric particle, useful for waste solidification.

FIELD OF THE TECHNOLOGY

The present disclosure relates generally to rapid solidification of coalcombustion residuals, and more particularly to improved coal combustionresiduals solidification devices, kits, systems and methods.

BACKGROUND

Coal combustion residuals (CCRs or collectively “coal ash”) are one ofthe largest industrial waste streams generated in the United States.Coal ash is a toxic laden waste, for example, generated as coal isburned for energy. Coal ash generally contains heavy metals and othertoxic remnants that become concentrated and gathered in the ash throughthe processing process. In 2012, more than 470 coal-fired electricutilities burned over 800 million tons of coal, generating approximately110 million tons of CCRs in the U.S. Storage and processing of CCRs is amajor undertaking and environmental release/exposure to coal combustionresiduals can be damaging to the environment, having toxic impacts onthe eco-system, and creating extremely exorbitant damage andremediation. Just in the Southeast alone, there are over 400 coal ashstorage facilities and over 50 documented contamination sites. At thesecontamination sites, there is often pollution to the ground and/orsurface water, some resulting in “high hazard” coal ash dams asdetermined by EPA assessment.

It is desirable to prevent the release of coal combustion residuals intothe environment and proper containment is an ongoing concern. In thecase of a coal combustion residual spill, it is imperative to providerapid, effective clean-up for the contamination and contaminated area.While some attempts have been made to address these issues, theyconventionally are expensive, and not highly efficient or effective.

CCRs may be considered, by way of example, fly ash, coal ash, bottomash, boiler slag and flue gas desulfurization, and/or scrubber,materials such as synthetic gypsum and the like, which are produced whencoal is burned for electricity generation.

CCRs may be generated wet or dry, and some CCRs are dewatered whileothers are mixed with water to facilitate transport (e.g., sluiced).Some of the CCRs can be beneficially utilized; however, large amounts ofCCRs are disposed in surface impoundments and landfills. Thus, CCRstypically are disposed in offsite and/or onsite landfills, or surfaceimpoundments. Generally, coal ash is collected and moved to large coalsludge lagoons or dry landfills for the ultimate storage.

Conventional methods for storage of coal ash in landfills and sludgelagoons attempt to indefinitely and safely store this toxic material inbins and behind dams. However, preserving the integrity of thesurrounding water supply and environment, presents demanding concerns,and often the coal ash storage mixture is able to leak into groundwaterand/or become released back into the water supply.

CCR Rules newly adopted in the U.S. require unlined CCR ponds to undergoexcavation, transport and disposal into lined landfills or in-situcapping. Because CCR ponds are open for relatively long periods of time,they contain a significant fraction of water. Some fly ash may display atendency to adhere to porewater in the layers of fly ash basinsrequiring more time to dewater and stabilize. During transport, the ashtends to release water and exhibit instability. If the excavated CCRfails the paint filter test, it cannot be disposed into a linedfacility. Managing water in CCR ponds can often require dewatering usingin-situ wells, stockpiling and allowing gravity drainage, or pumpinginto Geotubes. These options are all time consuming and expensive and,in some cases, these methods require treatment before the water is evendischarged.

Therefore, Applicants desire alternative cost-effective, more efficientand secure storage and remediation devices, kits and methods that aremore reliable in preventing release of CCRs into the environment whilebeing stored and/or provide improved remediation and clean-up ofaccidental environmental CCR exposure.

SUMMARY

In accordance with the present disclosure, coal ash waste devices,assemblies, systems, kits and methods are provided for packaging,storing, organizing, and solidifying coal ash wastes and the like. Thisdisclosure, in one embodiment, provides improved coal ash solidificationdevices, kits, assemblies and methods that are cost-effective,convenient, efficient, and safe for the user.

One example of the inventions of the present disclosure is directed to acomposition including a superabsorbent polymer for solidification ofCCRs. The composition may also include a second material. Thecomposition may be a blend of a SAP and a second blend item. A blend mayinclude one or more SAP.

A blend may include one or more SAP and another second blend item.

Other examples of the inventions of the present disclosure may bedirected to an absorbent structure containing a superabsorbent polymerand/or a superabsorbent polymer blend. Still other embodiments include amoisture absorbent polymer for moisture laden environmental wastes, byway of example CCRs. One example is directed to a moisture absorbentpolymer including a SAP, by way of example of crystals of sodiumpolyacrylate. The polymer may also include other second items, by way ofexample, in amounts of bentonite clay, Portland cement, and/or woodfibers in a moisture absorbent formulation (MAF). The moisture absorbentpolymer may instigate a waste solidification.

In some examples, non-polymeric particles may be added to an SAP inorder to increase the swellability of superabsorbent polymers. In suchan application, gel block may be desired and the particle mixture isdesigned to achieve gel block as a desired end result.

Additionally, the absorbent composition may include a sanitizer. Thesanitizer may be granular chlorine.

In other embodiments, the inventions of the present disclosure mayinclude a method of solidifying CCRs. In yet other embodiments, theinventions of the present disclosure may include a method of making acomposition for solidification of CCRs.

In some examples, the inventions of the present disclosure include asolidification system for environmental waste solidification. Thesolidification system includes a blend including an absorbent polymer.The absorbent polymer may include SAP. The SAP may be granular. The SAPmay be loose and dispensed from a bottle and/or a container. The SAP maybe housed in a packet. The packet may be configured to allow liquidpenetration. The packet in some examples may be made of dissolvablepolyvinyl alcohol and/or any other suitable water soluble film.

In some examples, the composition is considered the SAP mixture ofExamplel, Example 2, Example 3, Example 4, Example 5, and/or Example 6,individually and/or in combination.

An absorbent composition for environmental waste solidification in someembodiments includes: a population of superabsorbent polymer particles;a second item mixed with the population of superabsorbent polymerparticles; and wherein said absorbent composition absorbs moisture froman Ash waste, forms a solidified Ash mixture, the solidified Ash mixtureconfigured to pass a paint filter test.

Still other examples are considered a system for solidification ofmoistened Coal Ash, including: substantially between 0.5% and 2% of SAPby dry weight; and a material, when combined with moistened Coal Ashhaving a water moisture up to as high as about 75%, able to stand at anundrained shear strength ranging from about 2 to about 10 psi.

A system for solidification of moistened Coal Ash may include an amountof SAP. The SAP may be mixed with an amount of bentonite. In someexamples, SAP and about 50% bentonite form a blend. The blend may alsoinclude amount of Portland cement. The blend in some examples includesabout 50% SAP, about 25% Bentonite, and about 25% Portland cement. Theblend in other examples includes between about 70-80% SAP, between about5-10% bentonite, and between about 5-10% Portland cement. Still otherblends may include between about 5-10% wood flour. The SAP may becontained in power pellets. The power pellets may include, by way ofexample, between about 2-8% SAP. The SAP may be cross-linked internallyand on its surface. The amount of SAP may be contained inside a watersoluble packet.

The above summary was intended to summarize certain embodiments of thepresent disclosure. Embodiments will be set forth in more detail in thefigures and description of embodiments below. It will be apparent,however, that the description of embodiments is not intended to limitthe present inventions, the scope of which should be properly determinedby the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the disclosure will be better understood by a reading ofthe Description of Embodiments along with a review of the drawings, inwhich:

FIG. 1 is an example evaluation and results of the effect of MAFaddition on Undrained Shear Strength;

FIG. 2 shows one example of the amount of SAP in each compositiontested;

FIG. 3A-C are exemplary testing results of Fly Ash exposed to an SAPmaterial as disclosed herein;

FIG. 4A-C are graphs of exemplary Fly Ash samples exposed to compositionsamples in time increments as evaluated by pocket penetrometer, torvanetesting, an unconfined compression testing results according to examplesof the present disclosure;

FIG. 5A-B show exemplary Fly Ash samples after US testing;

FIG. 6A-C are graphs of exemplary Fly Ash samples exposed to compositionsamples in time increments as evaluated by pocket penetrometer, torvanetesting, an unconfined compression testing results according to examplesof the present disclosure;

FIG. 7A-C are graphs of exemplary Fly Ash samples exposed to compositionsamples in time increments as evaluated by pocket penetrometer, torvanetesting, an unconfined compression testing results according to examplesof the present disclosure;

FIG. 8A-C are graphs of exemplary Fly Ash samples exposed to compositionsamples in time increments as evaluated by pocket penetrometer, torvanetesting, an unconfined compression testing results according to examplesof the present disclosure;

FIG. 9A-C are graphs of exemplary Fly Ash samples exposed to compositionsamples in time increments as evaluated by pocket penetrometer, torvanetesting, an unconfined compression testing results according to examplesof the present disclosure;

FIG. 10A-C are graphs of exemplary Fly Ash samples exposed tocomposition samples in time increments as evaluated by pocketpenetrometer, torvane testing, an unconfined compression testing resultsaccording to examples of the present disclosure; and

FIG. 11 is a graph overview comparison of exemplary Fly Ash samplesaccording to inventions of the present disclosure tested according tounconfined compression testing.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the following description, like reference characters designate likeor corresponding parts throughout the several views. Also in thefollowing description, it is to be understood that such terms as“forward,” “rearward,” “left,” “right,” “upwardly,” “downwardly,” andthe like are words of convenience and are not to be construed aslimiting terms.

Referring now to the drawings in general, it will be understood that theillustrations are for the purpose of describing embodiments of thedisclosure and are not intended to limit the disclosure or any inventionthereto. Superabsorbants are known in the art as water-swellable,water-insoluble, organic or inorganic material capable of absorbing atleast about 100 times its weight in an aqueous solution. Superabsorbentpolymers are cross-linked, neutralized polymers which are capable ofabsorbing large amounts of aqueous liquids and body fluids, such asurine or blood, with swelling and the formation of hydrogels, and ofretaining them under a certain pressure in accordance with the generaldefinition of superabsorbent. The main use for internally cross-linkedsuperabsorbent polymers has been in sanitary articles. Some SAPs may beinternally and surface crosslinked. U.S. Pat. No. 7,291,674 to Kangaddresses surface cross-linking superabsorbent polymers in order toretain liquid retention, permeability, and gel bed strength whensuperabsorbent polymer is increased in percent by weight based on theabsorbent structure toward usage in sanitary dry articles, the referencebeing incorporated herein in its entire.

Applicant realized in the inventions as disclosed that Super AbsorbentPolymers (SAP), for example Sodium Polyacrylate, have the ability toreduce waste transportation costs by solidifying liquid waste whileminimizing an increase in weight and volume. SAPs have the capability ofsolidifying in some instances and under some conditions up to 300× itsweight in water. Applicant's inventions have benefits over other typesof conventional waste collection and solidification media in that SAPschemically bond with water and do not biodegrade and release liquidwaste, minimize waste volume, typical expansion is less than 1% andmixes quickly to improve production efficiency and to pass the EPA TestMethod 9095 paint filter test, and are approved for landfill use. Oneexample of the inventions of the present disclosure is directed to acomposition including a superabsorbent polymer for solidification ofCCRs. The composition may also include a second material. Thecomposition may be a blend of a SAP and a second blend item. A blend mayinclude one or more SAP. A blend may include one or more SAP and anothersecond blend item. Other examples of the inventions of the presentdisclosure may be directed to an absorbent structure containing asuperabsorbent polymer and/or a superabsorbent polymer blend. Stillother embodiments include a moisture absorbent polymer for moistureladen environmental wastes, by way of example CCRs. One example isdirected to a moisture absorbent polymer including a SAP, by way ofexample of crystals of sodium polyacrylate. The polymer may also includeother second items, by way of example, in amounts of bentonite clay,Portland cement, and/or wood fibers in a moisture absorbent formulation(MAF).

In some examples, non-polymeric particles may be added to an SAP inorder to increase the swellability of superabsorbent polymers. In suchan application, gel block may be desired and the particle mixture isdesigned to achieve gel block as a desired end result. In one example, acomposition for solidification of CCR wastes in contaminated sitesincludes a super absorbent polymer and a non-polymeric particle, inamounts to solidify the contaminates so as to pass the paint filtertest.

Additionally, the absorbent composition may include a sanitizer. Thesanitizer may be granular chlorine.

In other embodiments, the inventions of the present disclosure mayinclude a method of solidifying CCRs. In yet other embodiments, theinventions of the present disclosure may include a method of making acomposition for solidification of CCRs.

CCR may often require extraordinary removal measures, being upwardsof >50% moisture and often requiring either wet evacuation or dredgingprior to either dewatering or solidification. A bench-scale evaluationof multiple grades of blends including SAP was undertaken to achievebalance of cost and performance measures in treating CCR waste. Five wetCCR waste samples (Ash C, Ash A, Ash M1, Ash M2, and Ash U) were securedfrom different power utilities' CCR ponds. The water content at whichthe fly ash samples fail a paint filter test were measured. Exampleblends, including SAP, were tested for pre- and post-moisture content,specific gravity, bulk density, Vane Shear, Undrained Cyclic TriaxialTesting and Unconfined Compressive Strength. SAPs were tested, by way ofexample, ZapZorb SAP (available from Zappa Tec in McLeansville, NC) indifferential blends, by way of example, as below were tested:

Sample 1 (P100) included 100% SAP.

Sample 2 (P2) included a ZapZorb P2 Formulation—50% ZapZorb SAP+50%Bentonite.

Sample 3 (P4) included a ZapZorb P4 Formulation—50% ZapZorb SAP+25%Bentonite+25% Portland Cement.

Sample 4 (P6) included a ZapZorb P6 Formulation—75% ZapZorb SAP+8%Portland Cement+8% Bentonite+8% wood flour.

Sample 5 (PP) included Power Pellets formation comprising—5% ZapZorbSAP+95% wood pellets.

Sample 6 (P7) included 75% wood four+25% P100 ZapZorb SAP.

In the samples above, Samples 1, 2, and 3 were evaluated at least at 1%and 2% of dry mass fraction of fly ash; Sample 5 was evaluated at leastat 2%, 4% and 6% of dry mass fraction of fly ash; and Sample 6 wasevaluated at least at 2% and 4% of dry mass fraction of fly ash.

In one example, Fly Ash samples were tested at 70% water content andobserved to fail the Paint Filter Test. Fly Ash samples werecomparatively tested at 70% water content with 1% SAP added and observedto pass the Paint Filter Test.

In some examples, the inventions of the present disclosure include asolidification system for environmental waste solidification. Thesolidification system includes a blend including an absorbent polymer.The absorbent polymer may include SAP. The SAP may be granular. The SAPmay be loose and dispensed from a bottle and/or a container. The SAP maybe housed in a packet. The packet may be configured to allow liquidpenetration. The packet in some examples may be made of dissolvablepolyvinyl alcohol and/or any other suitable water soluble film. It canbe challenging to arrive at a compatible packet with both the contentsand the environment in which it will be dissolved. Examples of suchcompatible packets are dissolvable films that can be acquired fromMonoSol, LLC, such as their models M7031, M7061, M8534, and M8900(PXP6829) of water soluble film. Optionally, water soluble paper may beused. Packets may be made entirely of a dissolvable packet and/or mayinclude a dissolvable portion. The liquid solidifier may initially belocated within the packet and includes a plurality of surfacecross-linked superabsorbent polymer particles. The blend may alsoinclude a second item. The second item, by way of example, may bebentonite, Portland cement, wood flour, power pellets, and/or acombination of any or all. The absorbent composition may include asolidification of the desired materials. The solidification may be afirm solidification according to passage of Paint Filter Testing. Theblend may be considered a solidification blend. The blend may solidify awaste to a wetted solid state, the solid state of the waste being anon-flowing solid solidified from a flowable slurry state.

Test Methods/Testing Examples

Mineral Processing Services's (www.mpsmaine.com) full-scale specializedSmartFeed™ sequential mixer/blending unit is capable of metering ina >1%, by way of example, ZapZorb admixture, homogenizing/conditioningand stockpile discharging amended CCR waste or dredged sediment atbetween 50-100 tons/hr per unit—dependent upon material consistency andcs/o moisture. Testing shows that the duration of the sequentialblending of a 65% moisture CCR slurry to a solidified CCR matrix passingEPA Paint Filter criteria is as low as 3 minutes.

Advantages of blending low admixture, by way of example, as low as 0.5%ZapZorb admixture with the CCR waste and/or dredged sediment materialincludes improved assurance of passing EPA Paint Filter Test within 3minutes of blending (expediting direct load-out without the need forinterim stockpiles and rehandling expenses) and ensures no free liquidsare generated during OTR/rail transport prior to arrival at the finaldestination.

Also, advantages include significant improvement in UnconfinedCompressive Strength of the ZapZorb amended material for either supportof a final closure cap or to be bladed-out and compacted within amono-fill. Cost savings and time savings for the applications includedherein, in some examples, of 0.5% SAP blend for CCR solidification maybe dramatic cost reductions, shortened project schedules and minimizingof volume of CCR waste for transportation and storage.

The five coal fly ash samples from CCR ponds were secured from locationsin the southeastern portion of the U.S. and the water content at whichthe fly ash samples fail the paint filter test were measured. Thegravimetric water contents at which the ashes failed the paint filtertest ranged from 55% to 70% reported on dry basis. The MAFs were addedto the ashes at water content that was 5% more than the water content atwhich the ash failed the paint filter test, as seen below:

TABLE 1 Materials Used - Fly Ash 1. Fly Ash C (mwc¹ =70%; γ_(d) =60lbs/ft³) 2. Fly Ash A (mwc¹ =65%; γ_(d) =50 lbs/ft³) 3. Fly Ash M1 (mwc¹=60%; γ_(d) =54-58 lbs/ft³) 4. Fly Ash M2 (mwc¹ =58%; γ_(d) =55-58lbs/ft³) 5. Fly Ash U (mwc¹ =70%; γ_(d) =44-50 lbs/ft³) ¹mwc = moldingwater content is gravimetric water content on dry basis

The MAF was thoroughly mixed with the wet ash and samples were compactedusing modest compaction effort in a Proctor Compaction mold and aHarvard Miniature mold. After addition of the MAF, and when there was novisible water, the ash and all ash samples passed the paint filter test.The compressive and shear strengths of the samples were measured usingpocket penetrometer, Torvane, and using the Unconfined Compression testdevice. A majority of the samples passed the paint filter test within 15minutes after mixing the MAF. All samples showed modest to substantialincrease in compressive strength (See FIG. 1). The compressive strengthincreased from being zero when the sample was in liquid state to up to 3psi when one of the MAFs was added.

Shear strength as a function of water content was demonstrated withundrained shear strength (Ib/int) shown as to water content (%), withless water content in Ash samples having greater undrained shearstrength (36% Ash Sample: around 6.5 lb/in²; 46% Ash Sample: around 5.5lb/in²; 56% Ash Sample: around 4.5 lb/in²; % Ash Sample: around <1.0lb/in²).

Pocket Penetrometer (4″×4″ Sample with 15 mm foot) compacted usingProctor Compaction mold with Standard Proctor Hammer, 3 lifts, 10blows/lift.

Torvane testing (4″×4″ Sample with Largest vane) compacted using HarvardMiniature Compactor with 20 lb Spring Hammer, 3 lifts, 12 blows/lift.

Unconfined Compression Testing (1.25″×2.8″ Sample) with unconfirmedsample preparation and extrusion completed using Harvard Miniature Mold.Unconfined compression sample preparation and extrusion testing usingHarvard Miniature Mold.

EXAMPLES

Some embodiments of the inventions of the present disclosure are furtherillustrated by the following examples, not construed to be limiting inany way and are only exemplary thereof.

In some examples, the composition is considered the SAP mixture ofSample 1, Sample 2, Sample 3, Sample 4, Sample 5, and/or Sample 6,individually and/or in combination.

In some examples, the CCR Samples were tested and found as failing aPaint Filter Test in their natural state. The samples were evaluated formoisture in the Ash samples and a determination of the water content atwhich each of the ash samples failed the paint filter test.

The Specific Gravity of the CCR samples was as shown in TABLE 2 below:

TABLE 2 Specific Gravity of Fly Ash Samples Specific Gravity - FlyAsh 1. Fly Ash C (G = 2.391) 2. Fly Ash A (G = 1.801) 3. Fly Ash M1 (G =2.327) 4. Fly Ash M2 (G = 2.238) 5. Fly Ash U (G = 2.073)

FIG. 2 demonstrates the amount of SAP in the polymer samples tested.Pre-determined mass fractions of SAPs in compositions/blends were addedto CCR samples and evaluated for Paint Filter Test values, undrainedcohesion and shear strengths.

In some examples, the Ash Samples at 70% water content was demonstratedfailing a Paint Filter Test. Fly Ash at 70% water content+1% SAP wasdemonstrated passing the paint filter test.

In one example, FIGS. 3A-C show Fly Ash A and C with application ofExamples P100, P2, P4 and P6, individually. FIG. 3A shows specificallythe Pocket Penetrometer Result, indicating Average Undrained Cohesion(psi) at 1% and 2% example addition. FIG. 3B shows the Torvane Testingresult with Average Undrained Cohesion (psi) at 1% and 2% exampleaddition. FIG. 3C shows the effect of addition of at 1% and 2% of thevarious example SAPs on average unconfined shear strength (psi) at 1hour, 24 hours, 48 hours and 72 hours.

Other examples, in FIGS. 4A-4C show Fly Ash M1, M2 and U withapplication of Samples 1-P100, 3-P4, and 6-P7, individually. FIG. 4Ashows specifically the Pocket Penetrometer Result, indicating AverageUndrained Cohesion (psi) at 1%, 2% and 4% example addition. FIG. 4Bshows the Torvane Testing result with Average Undrained Cohesion (psi)at 1%, 2% and 4% example addition. FIG. 4C shows the effect of additionof at 1%, 2% and 4% of the various example SAPs on average unconfinedshear strength (psi) at 1 hour, 24 hours, 48 hours and 72 hours.

FIG. 5A-5B illustrate Fly Ash A and Fly Ash C Samples after UnconfinedCompression testing.

FIGS. 6A-6C illustrate Sample Fly Ash A exposed to Examples 1-5. Allresults with examples SAP addition performed better under PocketPenetrometer testing. Examples 2, 3, and 4 performed at higher levelunder Torvane Testing (see FIG. 6B) and 2, 3, 4 under UnconfinedCompression Testing over longer periods of time.

FIGS. 7A-7C illustrate Sample Fly Ash C exposed to Samples 1-5. Samples1-4 resulted in examples where SAP addition performed better underPocket Penetrometer testing. Samples 1, 2, 3, and 4 performed at higherlevel under Torvane Testing (see FIG. 7B) and also under UnconfinedCompression Testing over longer periods of time.

Sample Fly Ash M1 is shown exposed to Samples 1, 3 and 6 in FIGS. 8A-8C.Examples 1, 3 and 6 resulted in examples where SAP addition performedbetter under Pocket Penetrometer testing. Sample 3 performed at a higherlevel under Torvane Testing (see FIG. 8B) with 3 and 6 performinghighest under Unconfined Compression Testing over longer periods oftime.

FIGS. 9A-C illustrate Sample Fly Ash M2 exposed to Samples 1, 3 and 7.All samples resulted in examples where SAP addition performed betterunder Pocket Penetrometer testing. Various examples performed better atdiffering interval under Torvane Testing (see FIG. 9B) and all examplesperformed better under Unconfined Compression Testing over all timeperiods.

FIGS. 10A-C illustrate Sample Fly Ash U exposed to Samples 1, 3 and 7.All samples resulted in examples where SAP addition performed betterunder Pocket Penetrometer testing. Sample 3 performed best at all timeintervals under Torvane Testing (see FIG. 10B) and all samples performedbetter under Unconfined Compression Testing over all time periods.

All Fly Ash Samples are concurrently shown in FIG. 11 for UndrainedShear Strength when exposed to Samples 1, 3 and 6.

As little as 0.5% of SAP by dry weight was sufficient to stabilize themoisture in fly ash containing as high as 70% water. All example SAPsstabilized free water and the strength improved from a material that isat liquid limit to a material that can stand at undrained shear strengthranging from 2 to 10 psi. P2, P4 and P7 examples provided the moststrength for the amount of SAP they contained, respectively.

Applicant's inventions indicated a noticeable increase in stability,compressive strength and shear strength. Surprisingly, the percentage ofSAP in some instances was able to be reduced to less than one (1)percent and still maintain substantially the same stability, compressivestrength and/or shear strength. Even more surprising, in some instances,the strength and stabilization of the saturated fly materials actuallyincreased with the lower percentage of SAP.

In other examples, full-scale blending operational parameters for theaddition of SAP into a 65% moisture CCR slurry, showed that the additionof low-speed blending of 0.3% SAP was sufficient to solidify a CCRslurry in 3 minutes meeting EPA Paint Filter Criteria for no freeliquids. With such a lower percentage of the SAP, a blend can beapplied, by way of example, at 60 to 90 cubic yards per hour usingspecialized metering pumps, and/or with surface application methods likediscs and rotary mixers. The lower percentage SAP blend was shown toreduce leaching potential, stabilizing to control migration ofcontaminants at coal ash landfills, and controls/reduces the amount offree liquid present in transport prior to disposal.

Numerous characteristics and advantages have been set forth in theforegoing description, together with details of structure and function.Many of the novel features are pointed out in the appended claims. Thedisclosure, however, is illustrative only, and changes may be made indetail, especially in matters of shape, size, and arrangement of parts,within the principle of the disclosure, to the full extent indicated bythe broad general meaning of the terms in which the general claims areexpressed. It is further noted that, as used in this application, thesingular forms “a,” “an,” and “the” include plural referents unlessexpressly and unequivocally limited to one referent.

I claim:
 1. A system for solidification of moistened Coal Ash,comprising an amount of superabsorbent polymer (SAP) able to solidify anamount of given Coal Ash from a slurry to a solidified state able topass a Paint Filter Test, an amount of bentonite, an amount of cement,wherein the SAP, the bentonite, and the cement form a blend includingabout 50% SAP, about 25% Bentonite, and about 25% Portland cement.
 2. Asystem for solidification of moistened Coal Ash, comprising: an amountof superabsorbent polymer (SAP) able to solidify an amount of given CoalAsh from a slurry to a solidified state able to pass a Paint FilterTest, an amount of bentonite, an amount of cement, wherein the SAP, thebentonite, and the cement form a blend including between about 70-80%SAP, between about 5-10% bentonite, and between about 5-10% cement. 3.The system of claim 2 including between about 5-10% wood flour.
 4. Thesystem of claim 1 wherein the amount of SAP is contained in a pelletform.
 5. The system of claim 1 wherein the SAP is cross-linkedinternally and on its surface.
 6. The system of claim 1 wherein theamount of SAP is contained inside a water soluble packet.